Two years ago, Paul Mokbel was living in a condo at the Thompson Hotel and working mad hours to grow his software start-up, SiteScout. He was on the hunt for new corporate headquarters when he toured a four-storey property on Richmond Street near Spadina. “I remember taking in the high ceilings and thinking, man, I’d really love to live here,” he says. One year later, Mokbel sold his company for $40 million, launched a new career as an angel investor and started craving more privacy than his Thompson suite provided. Luckily, his dream home was still on the market. He bought the building for $3 million, leased out the lower floors to Nike and transformed the upper storeys into a cushy penthouse suite. Working with the firm Lux Design, he revamped the kitchen, replaced the pale maple floorboards with dark American oak and installed a gleaming floor-to-ceiling bar. Now it’s the perfect retreat: a huge upstairs office lets him separate work from play, and the open-concept main floor is great for entertaining—or just hanging out alone. The place is incredibly private: concrete floors and walls block out any street-level hubbub, a terrace off the kitchen is shielded by a tall brick wall, and Mokbel designed a futuristic security system to rival Fort Knox. “I call it The Compound,” he says.